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<h4> Back Reconstruction </h4>
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<p> Back reconstruction step is used to separate individual data-set components from 
the aggregate set of components calculated from the <a href="icatb_calculate_ica.htm">calculate 
ICA</a> step. Figure shows the process involved in back reconstruction step. </p>

<p class="style1"> <img border="0" src="images/icatb_back_reconstruct.jpg"> </p>
<p><strong>Calculation involved in back reconstruction step:</strong></p>
<p>Back reconstruction uses information from the <a href="icatb_data_reduction.htm">data reduction</a> and the
<a href="icatb_calculate_ica.htm">ICA</a> 
steps to reconstruct individual subject spatial maps and time courses. Spatial 
map is calculated by multiplying weights matrix and product of whitening matrix with 
the data. Time courses&nbsp;can be calculated by taking the product of dewhitening matrix with the pseudo inverse of weights matrix. These are saved as 
.mat files with suffixes as '_ica_br*' where * refers to the data-set count.</p>
<p>After the components are reconstructed, the units of spatial maps and time 
courses are in arbitrary units. The component maps and time courses can be 
scaled using <a href="icatb_scaling_components.htm">scaling components </a>step.</p>
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